Distribution of interstellar plasma in the direction of PSR B0525+21 from data obtained on a ground–space interferometer

• Published in: Astronomy reports Vol. 61; no. 6; pp. 513 - 520
• Main Authors: Andrianov, A. S., Smirnova, T. V., Shishov, V. I., Gwinn, C., Popov, M. V.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01.06.2017; Springer Nature B.V
• Subjects: Astronomy; Astrophysics; Estimation; Interferometers; Interferometry; Interstellar; Observations and Techniques; Physics; Physics and Astronomy; Plasma; Power law; Radio telescopes; Scattering angle; Telescopes
• ISSN: 1063-7729; 1562-6881
• DOI: 10.1134/S1063772917060014

Observations on the RadioAstron ground–space interferometer with the participation of the Green Bank and Arecibo ground telescopes at 1668 MHz have enabled studies of the characteristics of the interstellar plasma in the direction of the pulsar PSR B0525+21. The maximum projected baseline for the ground–space interferometer was 233 600 km. The scintillations in these observations were strong, and the spectrum of inhomogeneties in the interstellar plasma was a power law with index n = 3.74, corresponding to a Kolmogorov spectrum. A new method for estimating the size of the scattering disk was applied to estimate the scattering angle (scattering disk radius) in the direction toward PSR B0525+21, θ scat = 0.028 ± 0.002 milliarcsecond. The scattering in this direction occurs in a plasma layer located at a distance of 0.1 Z from the pulsar, where Z is the distance from the pulsar to the observer. For the adopted distance Z = 1.6 kpc, the screen is located at a distance of 1.44 kpc from the observer.